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AQA A-Level Chemistry (7405). No other course is covered yet.
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Calculate the amount, in moles, of sodium chloride, NaCl, present in 4.15 g.
Mr(NaCl) = 58.5
The division is the wrong way round
You have divided the wrong way round. Amount = mass ÷ Mr, so the mass goes on top.
Give the IUPAC name of the halogenoalkane CH3CH2CHICH2CH3.
2-iodopentane is a different compound, CH3CHICH2CH2CH3. Count along to the carbon that actually carries the I: 3-iodopentane.
In which block of the Periodic Table is silver, Ag?
The s-block is groups 1 and 2, the two columns on the far left — plus helium. Silver is in group 11, so it is d-block.
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